Systemic & cornea/lens fundamentals Flashcards
Scleroderma
Bottom line: dry eyes + conjunctival telangiectasias + tight eyelid skin (or blepharophimosis) + malignant HTN retinopathy = SCLERODERMA
malignant hypertensive retinopathy: retinal hemorrhages, hard exudates, cotton wool spots, retinal and optic disc edema, and tortuous vessels.
rheumatic disease that occurs in localized/systemic forms
typically in women in their 30’s-50’s
Si/Sx: skin thickening and tightening and also by vascular insufficency and vasospasm (Raynaud’s phenomenon). Other systemic manifestions: GERD, pulmonary fibrosis, cardiac fibrosis, myositis, and renal disease (frequent cause of death and is commonly assoc/w/malignant HTN & kidney failure)
Mnemonic: Dr. Raynaud, a tight-fisted (tight eyelid skin) malignant (HTN) female attending (demographic) finding out she has scleroderma is mad (dry red eyes - conj telangiectasis). She is scarred down (cardiac/pulm fibrosis) and is going to die of kidney dz.
Which of the following findings is considered the hallmark of corneal limbal stem cell deficiency?
corneal limbal stem cells are located in the BASAL layer (“at the base”) of the limbus in a region called the “palisades of Vogt,” which are a series of fibrovascular ridges perpendicular to the corneal margin. These ridges are located approximately 1-2 mm posterior to the limbus where the conjunctiva and Tenons capsule fuse. These limbal stem cells divide asymmetrically to produce one daughter cell and one stem cell. Thus, the stem cell population remains static in healthy corneas. The daughter cells differentiate and migrate to replenish the corneal surface. The corneal epithelium is completely regenerated in approximately 7 days.
The hallmark of limbal stem cell deficiency (LSCD) is the PRESENCE OF GOBLET CELLS IN K EPITHELIUM (please commit this high yield fact to memory!). To demonstrate the presence of these cells, the clinician can either perform an excisional biopsy of the corneal surface or impression cytology and use a PAS or ALCIAN BLUE stain for goblet cells. Impression cytology is typically preferred since it is easier to perform and less invasive. Impression cytology basically involves pressing a piece of nitrocellulose filter paper against the corneal surface and staining whatever cells stick to the paper with the aforementioned dyes. The presence of conjunctival epithelial cells (or their markers; e.g. cytokeratin 19) on the corneal surface from impression cytology is another sign of LSCD.
Clinical signs of LSCD are:
“effacement” or loss of the palisades of Vogt,
late staining of the corneal epithelium with fluorescein,
peripheral pannus or corneal neovascularization
meds & corneal stromal deposits
Gold, phenothiazines, and retinoids are known to cause corneal stromal deposits.
Mnemonic: Rich person (gold) with bad skin (retinoids) who is crazy (phenothiazines), saying that he can’t see (K stromal deposits), when he actually can.
SLK
SLK: characterized by inflammation of the superior tarsal and bulbar conjunctiva (PAPILLARY reaction, not follicular), a fine punctate staining of the superior cornea/limbus, and filaments of the superior cornea. The superior bulbar conjunctiva is typically redundant, and one can slide this portion of the conjunctiva over the superior corneal surface with a cotton-tipped applicator.
Si/Sx: foreign body sensation, pain, and occasionally photophobia especially if filaments are present. The cause of SLK is not known, but it is associated with thyroid disease (typically hyperthyroidism), keratoconjunctivitis sicca, and hyperparathyroidism.
“mechanical” theory: thought that the rubbing of the superior palpebral conjunctiva against the superior bulbar conjunctiva (i.e. too much friction) causes the signs of SLK.
Rx: aggressive dry eye treatment, 0.5-1% silver nitrate SOLUTION (NEVER silver nitrate sticks which can cause burns) to the superior palpebral conjunctiva, resection of the redundant superior conjunctiva, pressure-patching, therapeutic contact lenses, and thermal cauterization.
Mooren’s ulcer systemic assoc
Mooren’s ulcer = Hepatitis C
Fabry’s disease
Fabry’s disease (X-linked alphagalactosidase deficiency). Sphingolipoides.
Fabry’s disease is characterized by renal failure, peripheral neuropathy, and hyperkeratotic skin lesions, and vortex keratopathy (which you can also see in amiodarone, indomethacin, chloroquine, and chlorpromazine).
Mnemonic: A Faberge egg (Fabry’s) with sparkles (vortex keratopathy). Alas, this is a bad gift (as is Tay-sachs - both spingolipioides), as it comes with skin/nerve problems and kidney disease. It too, like ichthyosis is X-rated (X-linked) and a fabulous hunter (fabry/hunter).
Superior limbic keratoconjunctivitis systemic assoc
Superior limbic keratoconjunctivitis = autoimmune thyroid disease
OCP
stereotypical: dz of older women (> 60 yo). Likely starts earlier in life and is not Dx due to early subtle findings. Stage 1: subepithelial fibrosis Stage 2: fornix foreshortening Stage 3: symblepharon formation Stage 4: corneal surface keratinization Stage 5: ankyloblepharon
Dx: conj bx with immunohistochemistry
supportive Dx: circulating autoantibodies (anti-beta4) to target antigen (beta 4 peptide of alpha-6-beta-4 integrin)
Cogan’s systemic assoc
Cogan’s syndrome (autoimmune interstitial keratitis and hearing loss) = polyarteritis nodosa
Mnemonic: Cogan the cyclops was blinded (interstitial keratitis). He couldn’t hear & had vertigo, he punched noodles (polyarteritis nodosa)
generally occurs in young adults who have had an upper respiratory tract infection in the previous 1-2 weeks.
Rx: Topical steroids for keratitis and oral steroids for the auditory system.
Important to rule out syphilis as a cause of the eye findings.
HSV vs. HZV
Zoster = nummular (“coin shaped” stromal infiltrates), raised mucous epithelial plaques weeks s/p skin rash, SECTORAL iris atrophy. Herpes also clasically gives the MOST NEUROTROPHIC keratopathy.
Mnemonic: older patients are more likely to be rich (coin shaped/nummular) and more likely to work for a SECTOR. Old = bad, so most neurotrophic keratopathy.
Simplex = no nummular infiltrates or plaques, PATCHY iris atrophy
Schnyder crystalline corneal dystrophy systemic assoc
Mnemonic: gene Ubi(AD)1. AD inheritance
Schnyder crystalline corneal dystrophy = hyperlipidemia / hypercholesterolemia
Central corneal opacification w/subepithelial crystals, dense arcus lipoides. RARE, progressive, affects STROMA at all levels starting in CENTER. Mid-periphery is LAST to become involved. decreased K sensation.
AD 2/2 mutation in UBIAD1 (Ubia prenyltransferase domain containing protein 1)
path: stains with oil red O stain
Dx: in 20s/30s. Better VA in scotopic conditions (dilated pupil)
Mnemonic: Eric Schynder (who is in his 20s/30s) riding in a red sports car (oil-red O) around a circle, which catches your peripheral vision (SPARES periphery, just like K blood staining clears periphery first). He is a rare progressive centrist with bad cholesterol (or lipid in balding hair). He likes Uber best [UBi(AD)1].
3 main sphingolipidoses
Fabry dz, multiple sulfatase deficiency, generalized gangliosidosis
All have corneal verticillata
Tay sachs is also a sphingolipidoses but typicaly has cherry red spot
tetracyclines SE
cause birth defects, permanent staining of teeth in children (< 10 years old contraindicated), and GI upset/diarrhea.
Epinephrine SE
SE: headache, palpitations, arrhythmias. Black deposits (oxidation rxns)
CME in aphakic pts
Mnemonic: aphakic patients get so excited (epi) that they can’t C (see/CME)
macular corneal dystrophy (MCD) mutation
defect in carbohydrate sulfotransferase 6 (CHST6)
K grafts
tissue storage < 4 days
death-to-preservation time: 12-18 hrs
endothelial count > 2K
Mnemonic: 4x3 = 12
Mutations in locusl 5q31 (TGFB1) cause:
granular (groenouw type I), Reis-Bucklers, lattice type I, Avellino
gelatinous droplike dystrophy mutation
defect in tumor associated calcium signal transducer 2 (TACSTD2)
AR
diffuse subepithelial and stromal amyloid deposits
VERY COMMON - recurrent errosions, and recurrence of the dz s/p transplant (nearly 100%)
How long to wait for transplantation of stem cells
1 year after chemical injury.
MC findng in sarcoidosis
calcific band keratopathy.
Other findings: nummular keratitis, thickening of DM, deep stromal vascularization 2/2 chronic uveitis
MC finding in sarcoidosis pts with ocular inv: periphlebitis; granulomatous uveitis with mutton fat KP (2/3 individuals with ocular involvement)
chronic angular blepharoconjunctivitis
crusting/ulceration of skin at lateral canthal angle.
Moraxella lacunata
papillary/follicular rxn of the tarsal conj
% of pts develop 2ndary glaucoma with ocular melanocytes
10%
HEDS study - stress
no STATISTICALLY significant assoc/w/HSV outbreaks and environmental stress
Average tear volume of an adult
7-10 uL
drop from standard medication - dispenses 50 uL per drop
Scleromalacia perforans
aka necrotizing scleritis WITHOUT INFLAMMATION (rare to have eye pain). ABSENT blood vessels overlying sclera with thinning.
assoc/w/RA - rheumatoid factor = autoantibody directed against IgG
HEDS- topical antiviral in stromal keratitis arm
Topical trifluridine eyedrops used to prevent an outbreak of herpetic epithelial keratitis.
Rx for stromal keratitis (autoimmune): PF q2h and topical trifluridine 4x/day.
No benefit in adding PO acyclovir to topical PF and trifluridine
Corneal blood staining clearance
clears centripetally = clears peripherally first, then moves to the center of the cornea. Esp concerning for amblyopa in kids
Mnemonic: Red bloody car (RBC) driving around a circle is likely to catch your PERIPHERAL vision (clears peripherally first)
conditions associated with limbal stem cell deficiency
Congenital aniridia
Ectodermal dysplasia, sclerocornea, KID syndrome*, congenital erythrokeratodermia**.
chem injury, S-J, trachoma, surgery.
Dx: goblet cells in epithelium (impression cytology)
stem cells live in the BASAL layer of the limbal epithelium. Need 25-33% intact to prevent conjunctival epithelium from growing onto the cornea.
Mnemonic: don’t KID around (KID syndrome) with a white cornea (scleroK)
- KID syndrome (keratitis-ichthyosis-deaf)
- *erythrokeratodermia: widespread hyperker @ birth
Riley-Day syndrome
aka Familial dysautonomia*. AR. Ashkenazi FH, skin blotching, neurotropic keratopathy with DECREASED tearing when crying.
On DDx for enlarged corneal nerves
Mnemonic: Ms. Riley Day, the Jewish girl who believes in her family, who gets on your nerves (K nerves) and no sensation (neurotrophia). Her skin gets BLOTCHY when she tries to cry crocodile tears (decreased tearing when crying). But don’t dismiss her b/c she has real problems (dysautonomia) even though she is quiet (AR).
*disturbs cells in the autonomic nervous system, which controls involuntary actions such as digestion, breathing, production of tears, and the regulation of blood pressure and body temperature
Mooren’s ulcer
“clasically” assoc/w/
- helminithic infection (parasitic warms = tapeworms, roundworms, flukes)
- hepatitis C
NO SCLERAL INVOLVEMENT (unlike PUK)
Mnemonic: Ms. Lauren (Mooren) with worms crawling all over her eyes. She also has hepatitis C. However, she is cosmetically conscious, so she wants white eyes (no scleral involvement)
ichthyosis and cornea changes
X-linked ichthyosis = form with corneal opacities
(less common with K changes but the MC type of ichthyosis = Ichthyosis vulagaris AD)
Mnemonic: X-rated ichthyotic patient to get K opacities
Indications for washout with hyphema
IOP > 60 mm Hg x 2 days
IOP > 35 mm Hg x 7 days
IOP > 25 mm Hg x 1 day in sickle-cell pt
Mnemonic: 60 x 2, 35 x 7, 25 x 1.
Think: 6023 and 5725-1
Lofgren syndrome
sarcoidosis
hilar adenonopathy, erythema nodosum, iridocyclitis
Mnemonic: Sarah Lofgren with hilar adenomathy, red bumps (erythema nodosum), uveitis and Sarcoid
Heerfordt syndrome
uveitis, parotitis, fever, CN7 palsy
Mnemonic: The uveitic feverish (fever) talking (CN7) parrot (parotitis) is “here for it” (heredordt).
assoc/w/MGD
Oral retinoid therapy rosacea DBUT (decreased break up time = faster tear breakup) posterior telangiectatic vessels keratin plugging hyperemia of the eyelid margin
contributes to majority of eye’s reractive power
air-tear interface = provides most of the optical power of the eye
Anterior K: 49 D
Posterior cornea: -6 D
Total K: 43 D
Refractive power of lens = 19
Aqueous component of tears
lacrimal glands, Krause and Wolfring glands
Mnemonic: Krouching wolf crying wolf
Nerve branches most affected by herpes zoster
Dermatomes of thorax (T3-L3)
